China-based messaging app WeChat struck back at a high-profile critic on Tuesday and denied the company is storing users’ chat histories.

The app, developed by Chinese conglomerate Tencent Holdings Limited, is akin to a Swiss army knife for smartphone users in China. It allows users to chat and share updates but also book doctor’s appointments, pay utility bills, and find friends. Similar to Skype, the app has a VOIP service that allows users to call phones and landlines as well.

The app, enormously popular in China and closing in on 1 billion users, is not without controversy however.

The company on Tuesday was trying to downplay criticism by Li Shufu, the chairman of Zhejiang Geely Holding Group Co. Ltd. and Volvo Cars, who on Monday suggested Tencent was “watching all our WeChats every day.”

WeChat issued a response on Tuesday via its app:

“Conversation histories are only stored on the user’s smartphone, computer or other [user] terminals,” the company said, “WeChat will not use any content from user chats for big data analysis. Because of WeChat’s technical model that does not store or analyze user chats, the rumor that ‘we are watching your WeChat everyday’ is pure misunderstanding.”

The fact that WeChat, like many social media platforms in China, are subject to censorship by the government makes things complicated for WeChat to say the least. Companies there, especially in the last several years, have struggled to find a balance between censorship and privacy.

In September the Cyberspace Administration of China (CAC) followed through on a law introduced in June by levying heavy fines against Tencent, Baidu, and Weibo for failing to properly censor online content, including posts that “misinterpret government policy”, “twist the history of the Chinese Communist Party” and “flaunt excessive wealth.” That same month the administration introduced regulations designed to hold organizations accountable for breaches of content rules. Those regulations, put into effect October 8, requires Internet chat service providers record, monitor, and retain users’ chat records for at least six months and inform authorities if they come across users posting scams, rumors or politically sensitive material.

According to WeChat’s privacy policy the app may retain and disclose users’ information “in response to a request by a government authority, law enforcement agency or similar body made to us or any of our affiliate companies.”

Reignited tension around the app comes a few months after researchers with Citizen Lab, an interdisciplinary laboratory based at the Munk School of Global Affairs at the University of Toronto, found the app was heavily censoring keywords related to the Communist Party of China’s (CPC) National Communist Party Congress. While not entirely surprising, researchers said in November their findings lend credence to the idea that Tencent received proactive guidance from the Chinese government how to handle events of this nature.

"Given the sensitivity of the event and the results of our study it is clear that the company faced direct or indirect government pressure to ensure content was properly managed," the researchers wrote, "The broad range of censored content may be due to Tencent proactively over-blocking content around a topic it knows is highly sensitive to avoid official reprimands, or it may also be part of a wider government strategy to manage online discussions and public opinion."

Citizen Lab’s research followed up publication of a report by Amnesty International in 2016, that ranked Tencent and WeChat last out of 11 vendors – far behind Facebook, Google, and Apple – when it comes to encryption and privacy. The company “does not publish many details of measures to address issues around privacy or other human rights,” nor does it “appear to put in place strong forms of encryption on its messenger services,” according to the “For Your Eyes Only?” report. (.PDF)